We will work toward our goal of isolation of the collagenase gene from rabbit synovial fibroblasts. Messenger RNA will be isolated from cells stimulated to produce collagenase by treatment with phorbol myristate acetate (10 to the minus 8th power M; 0.0 microgram/ml) or crystals of monosodium urate (100 - 300 micrograms/ml) by oligo dT chromatography. We will then enrich for collagenase mRNA and use this enriched population as a cDNA probe to isolate the collagenase gene.